My concern is will I lose steering feel or turn-in precision with the wider front tires over current stock 245s. I'll also be going to R-comps and adding a BBK in a few weeks (I am so ready for those).

I had this same question several months ago when I was deciding on a track wheel/tire setup. See the threads from Feb-March 2011 for more info. I was also concerned about a 275 in the front in terms of steering feel and especially tramlining, but more so if I used it on a daily driver/street setup.

I ended up getting Forgeline 18x10" wheels through Turner Motorsport and using 275/35-18 Nitto NT01s all around. It was fantastic for this last season, which was my first full track season. Compared to the stock 245/265 PZero setup, the Nittos are a revelation--much better turn-in, braking confidence, and overall grip. I had assumed this was due in large part to the larger contact patch of the wider 275s up front, but see Richbot's reply in my thread "BF Goodrich R1 size question" in the track/autocross section from a few days ago--he makes the argument that the overall contact patch size stays the same, and only the shape changes. The great improvement in front-end grip in cornering and braking is therefore probably more attributable to the Nittos' R-compound stickiness and tread pattern (or lack thereof!).

In any case, I've been happy with the 275/35-18 NT01 setup on this car. I have taken advantage of the ability to rotate the tires around. When I notice the driver's front tire feathering more on the outside than the other tires (need more negative camber next season), I rotate it to the other side, and have also rotated front to back to even out wear.

I was curious to try the BFG R1 next season, and I would have just gone with a 275/35-18 square setup again, but I've seen that some people have done a 265/35-18 -- 285/30-18 staggered setup with that particular tire. That's why I posted the inquiry.

I have a set of 18X10 Apex wheels with 275/35 tires mounted. Since my track time is minimal these days, I bought street tires for them, Michelin PSS. I have only had one track weekend with them, and maybe 1K street miles. The advantages on track are what you would expect, and I was pleased with the setup. For street use, I’ll mention a few minor issues which may be of interest, or not. Tramlining and noise from the front is elevated a bit. Steering feel is probably slightly affected, but I expect your choice of tires might have at least as much effect there. With wheels of 25 offset, the fronts are out just a little too much for my taste, but I’m not sure the offset could be much more without inner clearance issues. And this is a subjective thing. I think the OE fitment is fine, whereas many seem to prefer sticking them out until the wheel bearings scream foul. Overall, I believe the 275 square setup is good, and the handling and rotation advantages outweigh the minor annoyances. I find the E92 M3 to be noticeably more neutral in handling than the E46, both stock, but I still appreciate the influence of the square setup.

Good info all around here. There is never a simple yes or no with these things, especially when it comes to something as subjective as steering feel. Everything else being equal, you would have higher steering effort and possibly less precise feedback. But everything else is never equal, and the difference may or may not be enough to notice.

At the track, I don't see much downside to it. On the street it may not feel as good depending on tire choice and personal preference.

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I have accepted a new position at Tire Rack and am no longer in the sales department. gary@tirerack.com is available to assist with M3 questions.

My concern is will I lose steering feel or turn-in precision with the wider front tires over current stock 245s. I'll also be going to R-comps and adding a BBK in a few weeks (I am so ready for those).

Any thoughts? Is that anything to worry about?

Thanks.

It is not something to worry about at all for a track setup. I'd only consider that on a street setup that sees no track time, and really that would not be the issue. I'd be more concerned with tramlining.

You're adding extra tire. Extra tire is more grip and more speed. Even if the steering felt more numb, you would be driving a car that is faster, which is what this is all about. Not all cars have the same steering feel either, and countless people are already making changes like this to all generation BMW M3's with positive results.

To put it in perspective, consider if you could ever imagine saying the following? "I sure am glad I didn't get the wider/faster tire setup, as I'm really enjoying my stock steering feel while I lose/turn slower laps than everyone else".

Your car will turn in better due to the extra front grip. The only thing to consider for a BBK is if it will clear your wheels. 380mm brembo's don't fit under most 18's. There are more wheels that can clear the stop tech 380mm kit though such as the ARC-8 wheel.

For the E9X M3 I would recommend you go with 275/35/18's over 265's if you're going with a square setup on 10" wheels.

I autocross my car regularly with the Houston BMWCCA chapter and occasionally with the SCCA. I have the Turner 18x10 Forgeline's, also. I ran 275/35x18 Dunlop Direzza Z-1 Star-spec's on them first. That was a fantastic combination. I don't see any loss in steering feel or turn-in. The extra rubber up front gives great grip. I just put on a set of Hankook RS-3's, also 275/35x18, for comparison. So far, thay have also been great. With the right wheel setup and good tires, I don't think you will go wrong with square 275/35x18's.

ive tried it before, with 275 all around. i much prefer 265/295 or anything staggered. unless your a noob who cant drive, this car has more oversteer problems when driven correctly, then understeer. it is made to understeer for the idiots. kingleh also prefers a staggered setup, he uses 265/295.

ive tried it before, with 275 all around. i much prefer 265/295 or anything staggered. unless your a noob who cant drive, this car has more oversteer problems when driven correctly, then understeer. it is made to understeer for the idiots. kingleh also prefers a staggered setup, he uses 265/295.

Right or wrong, this perception of the carís balance is in the significant minority. Obviously, the driver can force either extreme if that is the goal. But the static handling balance of a car is conventionally determined from steady-state throttle input on a skid pad. Iíve never seen an M3 that would oversteer in that scenario.

For the track the the 275's square on 10's are the way to go.My 11 with the ZCP is very neutral compared with my 08 which had a fair bit of oversteer on this setup.Not a very good street setup as it tramlines a lot on our well worn roads.Being able to rotate your track wheels will save you a lot of money in the long run.

I did have some initial qualms about the 275s up front re: potential rubbing of inner fender liner at less than full turning lock. When I switched to 255 ps2s from 245 on 19" plus 15mm spacer, I would rub consistently so that I had to take the spacer off. No biggie. I suppose the smaller diameter of the 18"s will compensate for the wider tire width, eh? Anyone have rubbing issues with this setup? I'm not lowered.

I did have some initial qualms about the 275s up front re: potential rubbing of inner fender liner at less than full turning lock. When I switched to 255 ps2s from 245 on 19" plus 15mm spacer, I would rub consistently so that I had to take the spacer off. No biggie. I suppose the smaller diameter of the 18"s will compensate for the wider tire width, eh? Anyone have rubbing issues with this setup? I'm not lowered.

Thanks again, all.

A 275/35 18 on a 18x10 @25P does not rub but sure is close on my stock ride height,stock camber ZCP car.Some of the tires are wider than others but it has not been a problem at all on my car.

Here is mine. I don't have any rubbing issues. I am lowered on RDS Springs and running a 15mm spacer in the back and moving up to a 20mm soon. Thinking on putting a 5mm spacer up front. Car handles better.